God, with friends like these – Barack Obama must be desperate for some enemies. First embarrassed by his favourite preacher, Jeremiah Wright, now Obama's had to publicly distance himself from his "favourite rapper" Ludacris. It just goes to show, you can't have lunch with anyone these days without getting a stomach ache.

According to the BBC and other media, the Obama campaign has denounced a new song by rapper Ludacris (lyrics here) criticising Obama's opponents. The Obama-supporting song called Politics as Usual goes on the offensive, literally, with Obama's rivals. "Hillary hated on you, so that bitch is irrelevant" is just one line. The rap also refers to George W Bush as "mentally handicapped" and suggests that Republican presidential candidate John McCain "don't belong in any chair unless he's paralysed".

While mild compared to other rap releases (I'm thinking of the newly platinum Lollipop by Lil Wayne), the language has nevertheless drawn condemnation from the Obama camp. "While Ludacris is a talented individual, he should be ashamed of these lyrics," Obama campaign spokesman Bill Burton said, in an email statement. He also called the song "outrageously offensive".

Obama has already said that he deplores the degraded state of hip-hop, so presumably had nowhere else to go on these lyrics. But hip-hop is a music of conflict, as is the rapper Ludacris, who I met in London when he came to promote his first mainstream single Fantasy, back in 2001. He was a gentleman who took me to lunch in Pizza Hut and then rapped a capella to me in Kensington Palace Gardens. His lyrics, however, are anything but – Fantasy glorifies the easy lay and the man's right to objectify – as does his second major hit She's a Ho.

Obama says he is a fan of hip-hop and after apparently praising Ludacris in private, his comments smack of panic and insincerity. "Said I handled my biz and I'm one of his favourite rappers" – says Ludacris, and during a Rolling Stone interview earlier this year, Obama also praised Jay-Z and Kanye West. Has he listened to the back catalogues of said rappers and now suddenly because of the word "bitch" he's outraged? Come on, I don't buy it.

Obama's gotta do what he's gotta do. This means he's a friend of Wrights, unless Wright is called a racist – then he's appalled. He's a friend of hip-hop, unless hip-hop is called offensive: then he's outraged. But in future, he's got to actually tackle some of the conflicts about being black and excluded, not just distance himself from the less palatable parts. He came close to a debate when his Father's Day speech was lambasted by Jesse Jackson. This could have been a moment to address some serious issues for African Americans and actually Afro-Caribbean communities around the world too. Aside from issues of misogyny, parenting and exclusion, the black man remains very much a misunderstood myth. His voice has, up to now, mostly only been available through the medium of rap. But now there is another voice – Obama's. Now is an opportunity to bring together the perspectives of black preachers like Wright, old-school civil rights campaigners like Jackson and young rap icons like Jay-Z, people who are products of their environments as much as Palestinian freedom fighters and Jewish settlers. To merely denounce these figures as racist, anachronistic or offensive will do nothing to dispel the sense of exclusion felt by many black people, not just in America but around the world.